Lung dendritic-cell metabolism underlies susceptibility to viral infection in diabetes

People with diabetes feature a life-risking susceptibility to respiratory viral infection, including influenza and SARS-CoV-2 (ref. 1), whose mechanism remains unknown. In acquired and genetic mouse models of diabetes, induced with an acute pulmonary viral infection, we demonstrate that hyperglycaemia leads to impaired costimulatory molecule expression, antigen transport and T cell priming in distinct lung dendritic cell (DC) subsets, driving a defective antiviral adaptive immune response, delayed viral clearance and enhanced mortality. Mechanistically, hyperglycaemia induces an altered metabolic DC circuitry characterized by increased glucose-to-acetyl-CoA shunting and downstream histone acetylation, leading to global chromatin alterations. These, in turn, drive impaired expression of key DC effectors including central antigen presentation-related genes. Either glucose-lowering treatment or pharmacological modulation of histone acetylation rescues DC function and antiviral immunity. Collectively, we highlight a hyperglycaemia-driven metabolic-immune axis orchestrating DC dysfunction during pulmonary viral infection and identify metabolic checkpoints that may be therapeutically exploited in mitigating exacerbated disease in infected diabetics.

Evaluation of practice change following SAFE obstetric courses in Tanzania: a prospective cohort study

Anaesthesia has been shown to contribute disproportionately to maternal mortality in low-resource settings. This figure exceeds 500 per 100,000 live births in Tanzania, where anaesthesia is mainly provided by non-physician anaesthetists, many of whom are working as independent practitioners in rural areas without any support or opportunity for continuous medical education. The three-day Safer Anaesthesia from Education (SAFE) course was developed to address this gap by providing in-service training in obstetric anaesthesia to improve patient safety. Two obstetric SAFE courses with refresher training were delivered to 75 non-physician anaesthetists in the Mbeya region of Tanzania between August 2019 and July 2020. To evaluate translation of knowledge into practice, we conducted direct observation of the SAFE obstetric participants at their workplace in five facilities using a binary checklist of expected behaviours, to assess the peri-operative management of patients undergoing caesarean deliveries. The observations were conducted over a 2-week period at pre, immediately post, 6-month and 12-month post-SAFE obstetric training. A total of 320 cases completed by 35 participants were observed. Significant improvements in behaviours, sustained at 12 months after training included: pre-operative assessment of patients (32% (pre-training) to 88% (12 months after training), p < 0.001); checking for functioning suction (73% to 85%, p = 0.003); using aseptic spinal technique (67% to 100%, p < 0.001); timely administration of prophylactic antibiotics (66% to 95%, p < 0.001); and checking spinal block adequacy (32% to 71%, p < 0.001). Our study has demonstrated positive sustained changes in the clinical practice amongst non-physician anaesthetists as a result of SAFE obstetric training. The findings can be used to guide development of a checklist specific for anaesthesia for caesarean section to improve the quality of care for patients in low-resource settings.

Lipid desaturation regulates the balance between self-renewal and differentiation in mouse blastocyst-derived stem cells

Stem cells are defined by their ability to self-renew and differentiate, both shown in multiple studies to be regulated by metabolic processes. To decipher metabolic signatures of self-renewal in blastocyst-derived stem cells, we compared early differentiating embryonic stem cells (ESCs) and their extra-embryonic counterparts, trophoblast (T)SCs to their self-renewing counterparts. A metabolomics analysis pointed to the desaturation of fatty acyl chains as a metabolic signature of differentiating blastocyst-derived SCs via the upregulation of delta-6 desaturase (D6D; FADS2) and delta-5 desaturase (D5D; FADS1), key enzymes in the biosynthesis of polyunsaturated fatty acids (PUFAs). The inhibition of D6D or D5D by specific inhibitors or SiRNA retained stemness in ESCs and TSCs, and attenuated endoplasmic reticulum (ER) stress-related apoptosis. D6D inhibition in ESCs upregulated stearoyl-CoA desaturase-1 (Scd1), essential to maintain ER homeostasis. In TSCs, however, D6D inhibition downregulated Scd1. TSCs show higher Scd1 mRNA expression and high levels of monounsaturated fatty acyl chain products in comparison to ESCs. The addition of oleic acid, the product of Scd1 (essential for ESCs), to culture medium, was detrimental to TSCs. Interestingly, TSCs express a high molecular mass variant of Scd1 protein, hardly expressed by ESCs. Taken together, our data suggest that lipid desaturation is a metabolic regulator of the balance between differentiation and self-renewal of ESCs and TSCs. They point to lipid polydesaturation as a driver of differentiation in both cell types. Monounsaturated fatty acids (MUFAs), essential for ESCs are detrimental to TSCs.

Distinct infrastructure of lipid networks in visceral and subcutaneous adipose tissues in overweight humans

BACKGROUND

Adipose tissue plays important roles in health and disease. Given the unique association of visceral adipose tissue with obesity-related metabolic diseases, the distribution of lipids between the major fat depots located in subcutaneous and visceral regions may shed new light on adipose tissue-specific roles in systemic metabolic perturbations.

OBJECTIVE

We sought to characterize the lipid networks and unveil differences in the metabolic infrastructure of the 2 adipose tissues that may have functional and nutritional implications.

METHODS

Paired visceral and subcutaneous adipose tissue samples were obtained from 17 overweight patients undergoing elective abdominal surgery. Ultra-performance LC-MS was used to measure 18,640 adipose-derived features; 520 were putatively identified. A stem cell model for adipogenesis was used to study the functional implications of the differences found.

RESULTS

Our analyses resulted in detailed lipid metabolic maps of the 2 major adipose tissues. They point to a higher accumulation of phosphatidylcholines, triacylglycerols, and diacylglycerols, although lower ceramide concentrations, in subcutaneous tissue. The degree of unsaturation was lower in visceral adipose tissue (VAT) phospholipids, indicating lower unsaturated fatty acid incorporation into adipose tissue. The differential abundance of phosphatidylcholines we found can be attributed at least partially to higher expression of phosphatidylethanolamine methyl transferase (PEMT). PEMT-deficient embryonic stem cells showed a dramatic decrease in adipogenesis, and the resulting adipocytes exhibited lower accumulation of lipid droplets, in line with the lower concentrations of glycerolipids in VAT. Ceramides may inhibit the expression of PEMT by increased insulin resistance, thus potentially suggesting a functional pathway that integrates ceramide, PEMT, and glycerolipid biosynthetic pathways.

CONCLUSIONS

Our work unveils differential infrastructure of the lipid networks in visceral and subcutaneous adipose tissues and suggests an integrative pathway, with a discriminative flux between adipose tissues.

Bilateral giant parathyroid adenoma in the absence of multiple endocrine neoplasia type 1

INTRODUCTION

Bilateral giant parathyroid adenoma in the absence of multiple endocrine neoplasia (MEN) type 1 is extremely rare and literature on this subject is limited.

CASE HISTORY

A 79-year-old man presented with acute kidney injury secondary to hypercalcaemia. Blood test results indicated primary hyperparathyroidism. Ultrasonography revealed bilateral parathyroid adenomas measuring 19.4mm x 19.5mm x 18.8mm (left) and 15.2mm x 18.3mm x 19.6mm (left) whereas on computed tomography, the measurements were 31mm x 20mm (left) and 30mm x 14mm (right). Intraoperatively, giant adenomas measuring 50mm x 25mm x 12mm (left, weighing 8.101g) and 48mm x 22mm x 10mm (right, weighing 7.339g) were identified and excised. Parathyroid hormone level dropped from 44.6pmol/l preoperatively to 8.9pmol/l postoperatively (normal range 1.3-7.6pmol/l). The patient was discharged with no complications.

CONCLUSIONS

We report a rare phenomenon where bilateral giant parathyroid adenoma occurred in the absence of MEN type 1. It highlights the importance of cross-sectional imaging in delineating the anatomy of adenomas as their size can be grossly underestimated by ultrasonography alone.

A shift in follicular fluid from triacylglycerols to membrane lipids is associated with positive pregnancy outcome

Follicular fluid (FF) is a liquid that surrounds the ovum. Its metabolite and, specifically, its lipid content have been associated with oocyte development. To characterize possible association between the lipid composition of FF and the outcome of pregnancy, we carried out a lipidomics study and compared the abundance of lipids from FF of patients with positive and negative outcomes. We found a differential lipid network wiring in positive-outcome FF, with a significant decrease (∼2 fold; P < 0.001) in triacylglycerol levels and higher accumulation (10-50%; P < 0.001) of membrane lipids groups (phospholipids and sphingolipids). In addition to this major metabolic alteration, other lipid groups such as cholesteryl esters showed lower levels in positive-outcome patients, whereas derivatives of vitamin D were highly accumulated in positive-outcome FF, supporting previous studies that associate vitamin D levels in FF to pregnancy outcome. Our data also point to specific lipid species with a differential accumulation pattern in positive-outcome FF that predicted pregnancy in a receiver operating characteristic analysis. Altogether, our results suggest that FF lipid network is associated with the oocyte development, with possible implications in diagnostics and treatment.-Shehadeh, A., Bruck-Haimson, R., Saidemberg, D., Zacharia. A., Herzberg, S., Ben-Meir, A., Moussaieff, A. A shift in follicular fluid from triacylglycerols to membrane lipids is associated with positive pregnancy outcome.

Spirulina maxima and its effect on antioxidant activity in fructose induced oxidative stress with histopathological observations

Diabetes mellitus is a metabolic disorder characterised by hyperglycemia and oxidative stress. The aim of the present study is to explore the antioxidant effect of Spirulina maxima in rat model along with the histopathological observations. Diabetes was induced by feeding 10% fructose solution orally to Wistar rats (n = 6) for 30 days, analysed for plasma blood glucose and the markers of the oxidative stress [catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS)]. These biochemical studies were associated with histopathological examination of liver and kidney sections. The microalga Spirulina maxima being rich in proteins and other essential nutrients is widely used as a food supplement. S. maxima at a dose of 5 and 10% per kg and the metformin (500 mg/kg) as reference drug were given orally for 30 days to the diabetic rats. Diabetic rats showed significant (p < 0.001) elevations in plasma blood glucose, thiobarbituric acid-reactive substances and significant reduction in catalase, superoxide dismutase and reduced glutathione activity. Oral administration of 5 and 10% aqueous extract of S. maxima for 30 days restored not only of blood glucose levels but also markers of oxidative stress. Histopathological observations of tissues manifested that the S. maxima administration had the protective and therapeutic effects against fructose-induced abnormalities in diabetic rats. It is concluded that S. maxima is effective in reinstating the antioxidant activity in addition to its antidiabetic effect in type 2 diabetic rats.

Spirulina maxima Protects Liver From Isoniazid and Rifampicin Drug Toxicity

Hepatotoxicity associated with isoniazid and rifampicin is one of the major impediments in antituberculosis therapy. The present study explored the prophylactic and therapeutic efficacies of Spirulina maxima in isoniazid and rifampicin induced hepatic damage in a rat model. Hepatic damage induced in Wistar rats by isoniazid and rifampicin resulted in significant alterations in biomarkers of liver function, namely, bilirubin, aspartate transaminase, alanine transaminase, alkaline phosphatase, and oxidative stress markers such as superoxide dismutase, catalase, glutathione, and thiobarbituric acid reactive substances. Co-administration of Spirulina maxima along with antituberculosis drugs protected liver from hepatotoxicity due to isoniazid and rifampicin. Administration of Spirulina maxima consecutively for 2 weeks to hepatodamaged animals resulted in restoration of hepatic function as evident from normalization of serum markers of liver function. Thus, the present study revealed remarkable prophylactic and therapeutic potential of Spirulina maxima. Co-administration of Spirulina maxima and antituberculosis drugs is advantageous as it provides extra nutritional benefit.

[Autoimmune epilepsy]

There is increasing recognition of an autoimmune origin of pharmacoresistant epileptic disorders. Besides the paraneoplastic limbic encephalopathies (LE), reports of syndromes of non-paraneoplastic LE are increasingly reported in the last 5-10 years. Three antibodies are now relatively well described: Voltage-gated potassium channels (VGKC), glutamic acid decarboxylase (GAD) and N-methyl-D-aspartate receptor-(NMDA) antibodies. We review clinical syndromes, associated imaging and laboratory findings. While most reports arise from adult populations, children and adolescents are also concerned as evidenced by increasing observations. Early recognition is mandatory, since early immunomodulatory treatment appears to be related to significantly better outcome.

Delineation of hypoxia versus inflammatory contributions to tissue injury by attenuation of G-alpha-i signaling (93.7)

The complement dependent pathology resulting from mesenteric ischemia/reperfusion insult instigates tissue injury in mesenteric and systemic organs. In this study the contribution of G-protein receptor signaling through G[alpha]i to stages of tissue injury is delineated. Global G[alpha]i inhibition, by PTX, attenuated mesenteric injury and production of lipid modulators such as leukotriene B4. Systemic inflammation was inhibited as assessed by lung tissue injury scores and monitoring cellular infiltrates. To delineate the role of G[alpha]i signaling in mesenteric versus systemic inflammatory responses, an inhibitor of pulmonary inflammatory chemotactic G[alpha]i signaling, anti-CXCR2 was used. As expected PTX and anti-CXCR2, abrogated pulmonary inflammation. In contrast, anti-CXCR2 was not effective in mitigating mesenteric injury. The results from global versus specific G[alpha]i inhibition in local and systemic injury indicate multiple mechanisms by which G[alpha]i signaling facilitate tissue injury. The G[alpha]i linked signaling effects of complement activation and chemokine induced migratory control are distinct and can be mitigated independently. Delineating which signals govern particular components of tissue injury will be useful in developing therapeutics which can control specific deleterious aspects of systemic inflammation after trauma while maintaining the protective aspects of complement activation.

Early assessment of brain maturation by MR imaging segmentation in neonates and premature infants

PURPOSE

We evaluated the impact of premature extrauterine life on brain maturation.

PATIENTS AND METHODS

Twelve neonates underwent MR imaging at 40 (39.64 +/- 0.98) weeks (full term). Fifteen premature infants underwent 2 MR imaging examinations, after birth (preterm at birth) and at 40 weeks (41.03 +/- 1.33) (preterm at term). A 3D MR imaging technique was used to measure brain volumes compared with intracranial volume: total brain volume, cortical gray matter, myelinated white matter, unmyelinated white matter, basal ganglia (BG), and CSF.

RESULTS

The average absolute volume of intracranial volume (269.8 mL +/- 36.5), total brain volume (246.5 +/- 32.3), cortical gray matter (85.53 mL +/- 22.23), unmyelinated white matter (142.4 mL +/-14.98), and myelinated white matter (6.099 mL +/-1.82) for preterm at birth was significantly lower compared with that for the preterm at term: the average global volume of intracranial volume (431.7 +/- 69.98), total brain volume (391 +/- 66,1), cortical gray matter (179 mL +/- 41.54), unmyelinated white matter (185.3 mL +/- 30.8), and myelinated white matter (10.66 mL +/- 3.05). It was also lower compared with that of full-term infants: intracranial volume (427.4 mL +/- 53.84), total brain volume (394 +/- 49.22), cortical gray matter (181.4 +/- 29.27), unmyelinated white matter (183.4 +/- 27.37), and myelinated white matter (10.72 +/- 4.63). The relative volume of cortical gray matter (30.62 +/- 5.13) and of unmyelinated white matter (53.15 +/- 4.8) for preterm at birth was significantly different compared with the relative volume of cortical gray matter (41.05 +/- 5.44) and of unmyelinated white matter (43.22 +/- 5.11) for the preterm at term. Premature infants had similar brain tissue volumes at 40 weeks to full-term infants.

CONCLUSION

MR segmentation techniques demonstrate that cortical neonatal maturation in moderately premature infants at term and term-born infants was similar.

Phase 2 study of high dose etoposide (VP16-213) in hepatocellular carcinoma

A phase II study of etoposide (VP16-213) in hepatocellular carcinoma was conducted among 18 Chinese patients. There was no observable tumour response but the treatment was relatively well tolerated with an overall median survival interval of 74 days.

A randomised cross-over trial comparing low-dose metoclopramide and chlorpromazine with high-dose metoclopramide in Chinese patients with advanced cancer receiving cisplatinum and 5-fluorouracil

Nineteen Chinese patients receiving chemotherapy for advanced cancer were studied for chemotherapy-induced acute nausea and vomiting. The chemotherapy consisted of cisplatinum 100 mg/m2 i.v. infusion over 4 h on day 1 and 5-fluorouracil (5-FU) 1000 mg/m2 120-h continuous infusion from day 2 to day 6, repeated every 3 weeks. At the first course of chemotherapy the patients were randomized to receive either low-dose metoclopramide and chlorpromazine or high-dose metoclopramide, and then crossed over for the second course. In the high-dose metoclopramide group there was a suggestion of an earlier onset of emesis, with slightly more frequent retching and vomiting and less food consumed. However, the duration of emesis was shorter in the high-dose group. These differences were not statistically significant. There were no major side effects. Mild salutary drowsiness was noticed in patients receiving low-dose metoclopramide and chlorpromazine. This trial suggests that, in the dosage, route and schedule described, high-dose metoclopramide is no more effective than low-dose metoclopramide together with chlorpromazine in preventing cisplatinum-induced nausea and vomiting. The low-dose scheme is more economic and suitable for patients with advanced cancer.